I've just received VS2 trigger frame from defjoker (thanks again man!). I needed only board and eyes, but it took me 5 sec to notice that layout of screws and sear between MR1 and VS2 is very similiar.
So, I've installed the frame on MR1 body and it fits very well. Front screw needs to be longer (about 5-7 mm), and there is a gap between frame and body. But, the inner contact surface (raised part on the frame that fits into recessed part of the body) fits so well that there is no free play at all, even with screws only fitted, not tightened.
Front part of VS2 frame extends over the front screw. Screw on MR1 is in front of the trigger guard, while on VS is inside of the trigger guard. That means you have to remove MR1 magazine / front grip. Cocking and trigger seems to be working OK, haven't tested yet.
Its made out of the plastic, and you can feel the diff, even with installed battery.
This is just a test, I'm not sure I'll use it like this, but looks and feels too good to keep idea just for myself

(Note: frame came without trigger and grip wraps, I've superimposed MR1's over VS2 with Paint Shop, just for the pic)